Mann, William  <br/><br/>
Mental Arithmetic / 
by William  Mann and et al... 
 - America :   Charles E. merrill publishing co,   1968. 
 - 47p. : 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Education
<br/><br/><label>Dewey Class. No.: </label>513   / MAN.M